I really doubt that anyone is buying bitcoin for the collapse of industrial civilization. The more prepper-case for bitcoin comes from either very high inflation, financial instability, and/or severe capital controls. It's not implausible that these conditions coexist with the continued existence of industrial civilization.
It's not implausible because it's happened many times before in history. For example, if you were a Jew in Germany circa 1936, Bitcoin would have been very very valuable to you. In much the same that diamonds were valuable to those in that time and place, because of the ease by which they could be hidden and smuggled against the authorities' wishes.